package demo1.demo2;

import java.util.LinkedList;
import java.util.Queue;
import java.util.Stack;

public class Test {
    public static void main(String[] args) {
        Queue<Integer> queue = new LinkedList<>();
        queue.offer(null);
        //queue.offer(123);
        System.out.println(queue.isEmpty());
        System.out.println(queue.poll());
        System.out.println(queue.poll());
        System.out.println(queue.poll());
        Stack<Integer> stack = new Stack<>();

    }
}
